A Geographical Analysis of the Family Ranunculaceae

Abstract

The Ranunculaceae Juss. are distributed worldwide. The primary differentiation of this family apparently took place in the vast territory of Eurasia during the Palaogene at least 50 million years ago or earlier, in Cretaceous time. The western and eastern floristic centers in eastern Asia played the most significant role in the secondary differentiation (i.e., formation of most genera and some groups of species), but important additional centers of ranunculaceous differentiation were in North and South America. The distribution of many groups of this family throughout the world and their local differentiation were associated with the general fall in temperature, development of the temperate floras, and the Alpine rise of mountain ridges (Neogene and more recent epochs).